Add raising exceptions to Worksheet#add_cell with too long cell conte…

…nts.

lib/rubyXL/worksheet.rb

@@ -1,5 +1,7 @@
 module RubyXL
   module LegacyWorksheet
+    TEXT_LENGTH_LIMIT_IN_CELL = 32767 # 2 ** 15 - 1
+
     include Enumerable
 
     def initialize(params = {})
@@ -50,9 +52,15 @@ def add_cell(row_index = 0, column_index = 0, data = '', formula = nil, overwrit
           case data
           when Numeric          then c.raw_value = data
           when String           then
+            if TEXT_LENGTH_LIMIT_IN_CELL < data.length
+              raise ArgumentError, "The maximum length of cell contents (text) is #{TEXT_LENGTH_LIMIT_IN_CELL} characters"
+            end
             c.raw_value = data
             c.datatype = RubyXL::DataType::RAW_STRING
           when RubyXL::RichText then
+            if TEXT_LENGTH_LIMIT_IN_CELL < data.to_s.length
+              raise ArgumentError, "The maximum length of cell contents (text) is #{TEXT_LENGTH_LIMIT_IN_CELL} characters"
+            end
             c.is = data
             c.datatype = RubyXL::DataType::INLINE_STRING
           when Time, Date, DateTime then

spec/lib/cell_spec.rb

@@ -66,6 +66,30 @@
       # We expect exactly the same date
       expect(cell.value.to_time.utc.iso8601).to eq(expected_datetime.iso8601)
     end
+
+    it 'should raise against too long String' do
+      ok_data = 'A' * 32767  # The limit is 32767
+
+      expect {
+         @worksheet.add_cell(0,1, ok_data) # 32767 -> OK
+      }.not_to raise_error
+      expect {
+         # 1 longer than the limit, so an exception must be thrown.
+         @worksheet.add_cell(0,2, ok_data + 'B')
+      }.to raise_error(ArgumentError)
+    end
+
+    it 'should raise against too long RichText' do
+      ok_data = 'A' * 32767  # The limit is 32767
+
+      expect {
+         @worksheet.add_cell(0,1, RubyXL::RichText.new(:t => RubyXL::Text.new(:value => ok_data))) # 32767 -> OK
+      }.not_to raise_error
+      expect {
+         # 1 longer than the limit, so an exception must be thrown.
+         @worksheet.add_cell(0,2, RubyXL::RichText.new(:t => RubyXL::Text.new(:value => ok_data + 'B')))
+      }.to raise_error(ArgumentError)
+    end
   end
 
   describe '.change_fill' do